It is desirable for small computing devices, by which we mean usually portable devices, such as lap-top-type computers and smaller, including mobile telephones, personal digital assistants, cameras and other devices, to be a small as possible for convenience.
The problem with making such devices small enough to carry is that it allows only a limited size for the interface. For example, in mobile telephones, a small screen and traditional numeric keypad are provided for the interface with the user. The numeric keypad input has been used for standard telephones for years, and was merely transferred for use in mobile phones with no significant adaptation. As mobile telephones become smaller and smaller, the traditional numeric keypad input becomes more and more difficult to operate. This is particularly the case where, as is usual for most mobile telephones today, it is required to input alphabetic characters in order to, for example, store contacts in the memory of the mobile telephone.
Further, the display screens provided for mobile telephones are, by necessity, also small where the phone is small. They are not able to provide, therefore, a view of a great deal of information at any one time.
There is a need for an improved interface for small computing devices, such as mobile telephone and PDAs.